.darkClass
{
z-index: 20;
filter: alpha(opacity=15); /*IE*/
opacity: 0.15; /* Safari, Opera */
-moz-opacity: 0.15;  /* FireFox */
background-color: black;
overflow: hidden;
height: 240px;
width: 320px;
background-image: url('../images/youtube-play.jpg');
background-repeat: no-repeat;
background-position:center;
}
